Body Condition Score in Cats: How to Check Your Cat’s Weight

What is a body condition score in cats?

A body condition score (BCS) is a practical way to assess how much body fat your cat has. It helps determine whether your cat is underweight, at an ideal body condition or carrying excess fat.

BCS is used alongside body weight in the veterinary profession because cats of the same breed or size can have different ideal weights. It assesses body fat, not muscle, so vets may also assess muscle condition separately.

How to check your cat’s body condition score

With your cat standing comfortably:

• Feel the ribs: Gently run your hands along both sides of the rib cage. You should be able to feel the ribs easily, with a slight covering of fat.

• Feel the waist: Run your hands along your cat’s sides towards the hips. You should be able to feel a slight waist behind the ribs.

• Look from above: Your cat should have a visible waist behind the ribs.

• Look from the side: The abdomen should slope upwards towards the hind legs. A loose flap of skin and fat (the primordial pouch) can be normal in many cats.

Long or thick fur can make visual checks harder, so feeling your cat’s body is important.

It’s best to ask your vet to double-check your cat’s score, as the differences between scores can be subtle, especially if you’re not used to assessing it. Your vet can also assess muscle condition separately, as a cat can carry excess body fat while still losing muscle.

Body condition score chart for cats

1 – Severely underweight

• Ribs: clearly visible from a distance

• Waist: extreme, with hip bones and spine sticking out

• Belly: tucked up very tightly

• Other: no fat anywhere and obvious muscle loss

2 – Underweight

• Ribs: very easy to see and feel

• Waist: extremely narrow

• Belly: very obvious tuck

• Other: spine and hip bones easy to see, with no fat covering

3 – Thin

• Ribs: easy to feel and may be slightly visible

• Waist: obvious

• Belly: clear tuck

• Other: bones along the lower back easy to see, with very little fat over the body

4 – Slightly lean

• Ribs: easy to feel, with only a very thin layer of fat; not visible

• Waist: clearly visible from above

• Belly: noticeable tuck

• Other: little or no fat on the belly

5 – Ideal

• Ribs: can be felt with a light touch under a thin layer of fat; not visible

• Waist: visible just behind the ribs

• Belly: gently tucked up

• Other: very little fat on the belly

6 – Slightly overweight

• Ribs: can be felt, but with a slightly thicker fat covering

• Waist: present but not obvious

• Belly: little or no tuck

• Other: small belly fat pad that is noticeable but not prominent

7 – Overweight

• Ribs: hard to feel under fat

• Waist: barely visible or absent

• Belly: slightly rounded, with no tuck

• Other: moderate belly fat pad

8 – Obese

• Ribs: cannot be felt without firm pressure

• Waist: none

• Belly: clearly rounded, with an obvious fat pad

• Other: noticeable fat over the lower back

9 – Severely obese

• Ribs: cannot be felt under heavy fat

• Waist: none, and the body looks round or oval from above

• Belly: very rounded and may sag

• Other: heavy fat over the lower back, face and legs

What is a healthy body condition score for cats?

A body condition score of 5 out of 9 is generally considered ideal for most cats. Scores below 4 suggest that a cat may be too thin, and scores above 5 suggest excess body fat. 

The ideal can vary with age, breed and health. Older cats, and cats with long-term conditions such as kidney disease, may be healthier carrying slightly more weight, around 5–6 out of 9, as they are more prone to losing weight and muscle. Kittens are still growing, so steady growth is a better guide than a particular score.

Body condition score measures fat, not muscle, so a cat can have an ideal score but still be losing muscle, especially as they get older. Your vet can help you work out the best body condition for your individual cat.

What to do if your cat has an abnormal body condition score

If your cat’s body condition score is below or above the ideal range, speak to your vet. They can assess your cat’s body fat and muscle condition and check for possible underlying medical causes. They can recommend a suitable plan to help them reach and maintain a healthy body condition.

If your cat is overweight, read our guide to obesity in cats for more information about the health risks and how to help your cat lose weight safely.

Seek urgent veterinary advice if your cat also seems unwell, for example, if they are lethargic, off their food, vomiting, have diarrhoea, or are drinking or urinating more than usual.

Remember: Body condition scoring is a useful guide, but it doesn’t replace a veterinary check. Your vet can assess your cat’s body condition alongside their muscle mass and overall health.

Our Joii Vets are available 24 hours a day for advice.